physical environment

what is climate

long term description of weather at a given location, based on averages and variation measured over decades.

or the long term trends in temperature, wind, and precipitation

what drives the climate system

radiation from the sun ultimately drives the climate system as well as biological energy production

what are the aspects of the physical environment

climate and chemical composition of air and water (salinity, acidity, and concentrations of gases in the atmosphere and dissolved in water)

what is weather

the current temperature, humidity, precipitation, wind, and cloud cover

what is climate variation

it includes the daily and seasonal cycles associated with changes in solar radiation as earth rotates on its axis and orbits the sun. it also includes changes over years or decades, such as large-scale cyclic weather patterns (El nino southern oscillation)

how does climate determine where organisms live

temperature determines rates of biochemical reactions and physiological activity for all organisms. ocean organisms depend on current, temperature, and water chemistry.

rain water is important. its an essential resource for land organisms and it maintains the quality of freshwater organisms

how can you characterize climate - or any aspect of the physical environment

by a given location by the average conditions and by its variability over time.

how does climate influence abiotic processes

climate affects the rate at which rocks and soil are broken down to supply nutrients to plants and microorganisms.

describe the process for solar radiation to reach earth

of the total solar radiation that earth receives a third of it is reflected back out by clouds, aerosols, and the earth’s surface. a fifth of the incoming radiation is absorbed by ozone, clouds, and water vapor in the atmosphere. the remaining half is absorbed by land and water at the surface.

what are aerosols

fine atmospheric particles

what happens when solar radiation is absorbed by earth’s surface

the solar radiaion absorbed by earth’s surface is emitted to the atmosphere as infrared radiation

how can earth’s surface cool

earth’s surface can lose energy and cool when water evaporates, because the phase change from liquid to water vapor absorbs energy

what is latent heat flux

the heat loss due to evaporation

what is conduction

the transfer of energy through the exchange of kinetic energy by molecules in direct contact with one another

what is convection

the transfer of energy by the movement of currents of air (wind) and water

what is sensible heat flux

the energy transfer from the warm air immediately above earth’s surface to the cooler atmosphere by convection and conduction is known as sensible heat flux

what are greenhouse gases

gases in the atmosphere that absorb and reradiate infrared radiation

what are the greenhouse gases

• water vapor (H2O)

• carbon dioxide (CO2)

• methane (CH4)

• nitrous oxide (N2O)

why is it hotter at the equator and colder at the poles

near the equator, the sun’s rays strike earth’s surface perpendicularly. toward the north and south poles, the angle of the sun’s rays becomes steeper, so the same amount of energy is spread over a progressively larger area of earth’s surface.

• because of the angle the sun hits earth

• because of how long the radiation has to travel through the atmosphere

why does uplift happen

the heating of earth’s surface varies with latitude and topography. such differential warming creates pockets of warm air surrounded by cooler air. when the warm, less dense air is surrounded by cooler denser air it will rise.

what is atmospheric pressure

its the force exerted by molecules of air on the air and surface below it

what happens to atmospheric pressure with altitude

atmospheric pressure decreases with increasing altitude

what happens when atmospheric pressure decreases

as the pocket of warm air rises it will expand. this expansion will cool the rising air because cool air cannot hold as much water vapor as warm air. so as the air continues to air continues to rise and cool water vapor will condense into droplets and form clouds

why dont clouds form past the stratosphere

cloud rise when warm air is surrounded by cool air. The air in the troposphere is cool, but the air in the stratosphere is warm. this creates a boundary where the air pocket stops rising

explain the circulation of air in a hadley cell

the warm air of the tropics cause the air to rise. it will rise until it reaches the boundary between troposphere and stratosphere where it will move towards the poles. here the air will cool down and once the air temperature and atmosphere temperature are the same the air falls back to the surface.

what is subsidence

its the process for air to descend back towards earth’s surface in a circulation cell

what does subsidence result in

subsidence creates areas of high atmospheric pressure around latitude 30N 30S, which prevent cloud formation and cause these areas to be very dry.

what is a hadley cell

its the circulation cell that is formed by the uplife of war air at the equator

what is a polar cell

circulation cell that occurs at the north and south pole

how does a polar cell work

cold, dense air subsides at the poles and moves toward the equator when it reaches the surface.

what is a ferrell cell

its the intermediate circulation cell between the hadley and polar cell

what drives the ferrell cell

the ferrell cell is driven by the movement of the hadley and polar cells and by exchange of energy between tropical and polar air masses at the polar front

how do prevailing winds occur

winds flow from high pressure areas to low so because of atmospheric circulation cells these areas of high and low pressures are constant which creates these constant patterns of wind

explain the coriolis effect

to an observer on earth’s surface rotating around the planetary axis, the path of the wind appears curved.

or

the apparent deflection of moving air and water currents caused by earth's rotation. because earth rotates faster at the equator than at higher latitudes, moving air or water retains its rotational momentum, causing it to deflect to the right in the northern hemisphere and to the left in the southern hemisphere relative to an observer on earth's surface.

why are seasonal air temperature changes less extreme over oceans than on land

because water has a higher heat capacity than land, so it can absorb more energy without its temperature rising. So ocean waters will remain cooler than land in summer, but warmer than land in the winter. and air temperatures near the ocean will follow this trend

why are ocean currents similar to prevailing winds

because of the coriolis effect. from an observer on earth, the water is deflected to the right in northern hemisphere and to the left in southern hemisphere.wh

why don’t the surface and deep layers of ocean water mix

because of differences in their temperature and salinity.

the surface waters are warmer and less saline, and therefore less dense, than the deeper, cooler ocean waters.

how does downwelling occur

when warm tropical surface currents reach polar regions, the water loses heat to the surrounding environment and becomes cooler and denser. when the water cools enough to form ice, the remaining water will increase in salinity which will then sink to deeper layers.

how does upwelling occur

when prevailing winds blow nearly parallel to a coastline. the force of the wind, in combination with the coriolis effect, causes surface waters to flow away from the coast and deeper, colder waters rise to replace them.

how can the coriolis effect create zones of upwelling

as a result of the coriolis effect, water just to the north and south of the equator is deflected slightly away from the equator, causing divergence of surface water and a zone of upwelling

why are upwelling zones among the most productive open ocean ecosystems

when organisms in the surface water dies, their body and all the nutrients they contain, sink and accumulate in deep water. upwelling brings these nutrients back

what is the great ocean conveyor belt

a large system of interconnected surface and deep ocean currents that links the pacific, Indian, and Atlantic oceans. it is an important means of transferring heat to the polar regions.

what 3 influences alter the global pattern of temperature

ocean currents, the distribution of land and water, and elevation

how does the ocean current influence temperature

ocean currents contribute to a warm climate in northern Europe than at North American locations of the same latitude

why are colder climates found at higher elevations

1. there are less air molecules to hold onto the infrared energy reflecting off the earth

2. air exchanges more effectively with cooler air in the surrounding atmosphere

why is the air cooler at higher altitudes

the atmosphere is warmed by infrared radiation emitted by earth’s surface, so the temperature of the atmosphere decreases with increasing distance from the ground

what is lapse rate

the decrease in temperature with increasing height above the surface